Habitat: Ammi visnaga is native to Europe, Asia, and North Africa, but it can be found throughout the world as an introduced species.It grows in fields and sandy places.Description:
Ammi visnaga is an annual or biennial herb growing from a taproot erect to a maximum height near 80 centimeters. Leaves are up to 20 centimeters long and generally oval to triangular in shape but dissected into many small linear to lance-shaped segments. The inflorescence is a compound umbel of white flowers similar to those of other Apiaceae species. The fruit is a compressed oval-shaped body less than 3 millimeters long. This and other Ammi species are sources of khellin, a diuretic extract.

It is in flower from Jul to September. The flowers are hermaphrodite (have both male and female organs) and are pollinated by Insects.The plant is self-fertile.

Cultivation:
Prefers a well-drained soil in a sunny position, succeeding in ordinary garden soil. Tolerates a pH in the range 6.8 to 8.3. This species is not fully winter-hardy in the colder areas of Britain, though it should be possible to grow it as a spring-sown annual. This plant is sold as toothpicks in Egyptian markets.

Chemical constituents:
Khellin, a chemical obtained from Ammi visnaga gives rose red color with KOH (solid) or NaOH & 2-3 drops of water, was used at one time as a smooth muscle relaxant, but its use is limited due to adverse side effects. Amiodarone and cromoglycate are derivates of khellin that are frequently used in modern medicine.

The chemical visnagin, which is found in A. visnaga, has biological activity in animal models as a vasodilator and reduces blood pressure by inhibiting calcium influx into the cell.Medicinal Uses:
Antiarrhythmic; Antiasthmatic; Antispasmodic; Diuretic; Lithontripic; Vasodilator.

Visnaga is an effective muscle relaxant and has been used for centuries to alleviate the excruciating pain of kidney stones. Modern research has confirmed the validity of this traditional use. Visnagin contains khellin, from which particularly safe pharmaceutical drugs for the treatment of asthma have been made. The seeds are diuretic and lithontripic. They contain a fatty oil that includes the substance ‘khellin’. This has been shown to be of benefit in the treatment of asthma. Taken internally, the seeds have a strongly antispasmodic action on the smaller bronchial muscles, they also dilate the bronchial, urinary and blood vessels without affecting blood pressure. The affect last for about 6 hours and the plant has practically no side effects. The seeds are used in the treatment of asthma, angina, coronary arteriosclerosis and kidney stones. By relaxing the muscles of the urethra, visnaga reduces the pain caused by trapped kidney stones and helps ease the stone down into the bladder. The seeds are harvested in late summer before they have fully ripened and are dried for later use.
In Egypt, a tea made from the fruit of this species has been used as an herbal remedy for kidney stones. Laborarory rat studies show that the extract slows the buildup of calcium oxalate crystals in the kidneys and acts as a diuretic.
This plant and its components have shown effects in dilating the coronary arteries. Its mechanism of action may be very similar to the calcium channel-blocking drugs. The New England Journal of Medicine writes “The high proportion of favorable results, together with the striking degree of improvement frequently observed, has led us to the conclusion that Khellin, properly used, is a safe and effective drug for the treatment of angina pectoris.” As little as 30 milligrams of Khellin per day appear to offer as good a result, with fewer side effects. Rather than use the isolated compound “Khellin,” Khella extracts standardized for khellin content (typically 12 percent) are the preferred form.

A daily dose of such an extract would be 250 to 300 milligrams. Khella appears to work very well with hawthorn extracts. An aromatic herb which dilates the bronchial, urinary and blood vessels without affecting blood pressure.

Visnaga is a traditional Egyptian remedy for kidney stones. By relaxing the muscles of the ureter, visnaga reduces the pain caused by the trapped stone and helps ease the stone down into the bladder. Following research into its antispasmodic properties, visnaga is now given for asthma and is safe even for children to take. Although it does not always relieve acute asthma attacks, it do3es help to prevent their recurrence. It is an effective remedy for various respiratory problems, including bronchitis, emphysema, and whooping cough. In Andalusia in Spain, the largest and best quality visnaga were employed to clean the teeth. Khella is the source of amiodarone one of the key anti-arrhythmia medications. The usual recommendation calls for pouring boiling water over about a quarter-teaspoon of powdered khella fruits. Steep for five minutes and drink the tea after straining.

Its active constituent is khellin, a bronchiodilator and antispasmodic that makes it useful for asthma sufferers It’s best used to prevent asthma rather than to counter an attack and can be taken on a daily basis with no contraindications. Because khella builds up in the blood, its use can be decreased after a period of time. Khella is safer than ma huang (ephedra) for asthma sufferers because it’s nonstimulating and nonenervating. Unlike ma huang, it doesn’t rob the body, especially the adrenals, of energy.

Spasmolytic action of khellin and visnagin (both furanochromones) is indicated for treatment of asthma and coronary arteriosclerosis.
An extract from khella (Ammi visnaga) is so far the only herb found to be useful in vitili. Khellin, the active constituent, appears to work like psoralen drugs?it stimulates repigmentation of the skin by increasing sensitivity of remaining pigment-containing cells (melanocytes) to sunlight. Studies have used 120-160 mg of khellin per day. Khellin must be used with caution, as it can cause side effects such as nausea and insomnia.

Another use is for vitiligo (an extract from ammi visnaga appears to stimulate repigmentation of the skin by increasing sensitivity of remaining pigment containing cells, melanocytes to sunlight)

Other Uses: The fruiting pedicel is used as a toothpick whilst the seeds have been used as a tooth cleaner

Known Hazards : Skin contact with the sap is said to cause photo-sensitivity and/or dermatitis in some people. Avoid during pregnancy and lactation. Avoid if on warfarin or other blood thinning medication. Prolonged use may lead to: constipation, appetite loss, headaches, vertigo, nausea and vomiting.

Disclaimer : The information presented herein is intended for educational purposes only. Individual results may vary, and before using any supplement, it is always advisable to consult with your own health care provider.Resources:
http://en.wikipedia.org/wiki/Ammi_visnaga
http://www.pfaf.org/user/Plant.aspx?LatinName=Ammi+visnaga
http://www.sarahraven.com/flowers/plants/cut_flower_seedlings/ammi_visnaga.htm